The most common geometric arrangement for front wheels of trucks and heavy duty motor vehicles comprehends defining left and right converging oblique axes about which the front wheels pivot to steer the vehicle. These axes are defined by a component denominated the kingpin. The kingpin extends between two spaced apart bearing structures extending from a steering knuckle and pivotally couples it to an end of the front axle. The steering knuckle includes a spindle upon which a front tire and wheel are rotatably supported and secured and a flange to which a front brake assembly is mounted. Each end of the front axle includes an eye which receives the kingpin and defines the pivot axis of the steering knuckle. Thrust bearings are disposed between each of the bearing structures and the end of the axle. The steering knuckle also includes an attachment feature to which a component of the steering mechanism, such as the Pittman arm or a tie rod, is attached.
Given the portion of the vehicle weight carried by the front tires, the expected and often exceeded service life of the vehicle and various road hazards, it is not surprising that the kingpin bearings deteriorate, allowing excessive play in the front wheel suspension which slowly renders the steering unsafe and causes excessive tire wear.
Given the direct cost of replacing the steering knuckle wherein frequently only the kingpin bearing surfaces have deteriorated, and the indirect cost related to the vehicle downtime, it is understandable that various repair methods have been proposed. For example, in U.S. Pat. No. 4,969,246, repair of the bearing portion within the axle is described. The axle end or eye is tightly engaged by a fixture which facilitates on-site repair of the axle eye. While this method and apparatus offered a simplified repair process and reduced the cost of repairing axle bearing failures, primarily due to its on-site capability, it did not address how repair of the more frequently worn or damaged bearings in the steering knuckle could be achieved. The present invention is so directed.